C! All you have to do is substitute the numbers into the problem!
Part A:

The first step of completing the square is writing the expression

as

which expands to

.
We have the first two terms exactly the same with the function we start with:

and

but we need to add/subtract from the last term, 49, to obtain 41.
So the second step is to subtract -8 from the expression

The function in completing the square form is

Part B:
The vertex is obtained by equating the expression in the bracket from part A to zero


It means the curve has a turning point at x = -7
This vertex is a minimum since the function will make a U-shape.
A quadratic function

can either make U-shape or ∩-shape depends on the value of the constant

that goes with

. When

is (+), the curve is U-shape. When

(-), the curve is ∩-shape
Part C:
The symmetry line of the curve will pass through the vertex, hence the symmetry line is

This function is shown in the diagram below
Answer:
35 [$]
Step-by-step explanation:
1) if Peter's sum is p and Jacky's is j, then the ratio 5:2 in the condition can be written j/p=5/2;
2) the phrase 'after Jacky gave 15 dolls to Peter, they have an equal number of dolls' can be written as j-15=p;
3) using the two above it is possible to make up the system of two equations:

4) finally, the have together 10+25=35 doll-s.
Franks plan is proportional because it goes through the orgin and Allie's plan doens't